[The Electrician]

That is simply an incorrect translation by the AP. This story has been getting a lot of "play" by the Japanese media, and even though I'm not much more that a beginner in understanding Japanese, I'm pretty sure that the NHK TV reports clearly identified the perp as a middle-school student, not a high-school student.

[farmfriend]

That would make sense. I was assuming that their school names where not necessarily the same as ours.